On a habitat structure-based approach to evaluating species occurrence: cavity-nesting Hymenoptera in a secondary tropical forest remnant

Abstract: Many tropical anurans use forest streams to deposit their eggs, but resource use and selection by tadpoles in tropical forests are poorly known. In the present research, we hypothesized that leaf litter and water depth affect tadpole assemblages due to adult habitat selection for oviposition and/or microhabitat selection by tadpoles. Fieldwork was carried out in the Estação Biológica de Boracéia, an Atlantic Rainforest reserve in São Paulo state, southeastern Brazil. We sampled tadpoles during a year using 40 double-entry funnel-traps distributed along four streams in the forest. Only leaf litter effects are species dependent. We discussed that habitat structure significance depends on the morphological and ecological adaptation to forage and avoid competition within the tadpole community.

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Leaf phenological traits of the tree fern Cyathea praecincta (Cyatheaceae) in a Brazilian lowland tropical forest

Australian Journal of Botany ◽

10.1071/bt18084 ◽

2018 ◽

Vol 66 (8) ◽

pp. 618 ◽

Cited By ~ 1

Author(s):

Mayara Magna Silva ◽

Rafael de Paiva Farias ◽

Lucas Erickson Nascimento da Costa ◽

Iva Carneiro Leão Barros

Keyword(s):

Tropical Forest ◽

Climatic Variability ◽

Dry Season ◽

Leaf Expansion ◽

Tree Fern ◽

Leaf Production ◽

Lowland Tropical Forest ◽

Tree Ferns ◽

Forest Remnant ◽

Reproductive Processes

Phenological studies are fundamental to our understanding of how the environment can influence plant growth and reproductive processes. Environmental triggers of fern phenology are poorly known. We investigated the leaf phenological traits of the tree fern Cyathea praecincta (Kunze) Domin in a Brazilian lowland tropical forest with a short dry season. We monitored 47 plants over an 18-month period, measuring leaf production, leaf fertility, leaf mortality and the relation of these variables with rainfall and temperature. Data on leaf expansion and lifespan were also presented. Full leaf expansion in C. praecincta took up to 3 months. The production of sterile and fertile leaves showed dissimilar interactions with climate, a common pattern among most tree ferns studied worldwide. Whereas production of sterile leaves of C. praecincta was not influenced by climatic variability, leaf fertility was driven by increasing rainfall. Some fertile plants (30%) produced exclusively fertile leaves and attained full maturity, playing a key role in the maintenance and growth of the population. The estimated leaf lifespan was 17.9±5.89 months. The finding that leaf mortality was driven by decreasing rainfall is in contrast with most tree ferns, which are not influenced by climate. None of the phenological variables was influenced by temperature. We demonstrated that rainfall plays a crucial role on leaf fertility and leaf mortality of C. praecincta in a tropical forest remnant with a short dry season and inversely related rainfall and temperature.

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